The act of picking up younger sexual partners as they are known to be sexually naive and impressed by age.
Some associated titles may be "cougar" for ladies hunting younger men, or "manther" for older men hunting younger ladies. Usually large sums of money in a subsequent bank account is required for the latter.
"Lads, see Hugh getting the shift off Eimear? He's old enough to be her dad."
"That is some fine fresh hunting."